Forest cockchafer
| Forest cockchafer | ||||||||||||
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Forest cockchafer, both ♂ ( Melolontha hippocastani ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Melolontha hippocastani | ||||||||||||
| Fabricius , 1801 |
The wood cockchafer ( Melolontha hippocastani ) is a beetle from the scarab beetle family (Scarabaeidae). He is after the cockchafer ( Melolontha melolontha ), the second most common species of the genus of beetle ( Melolontha ) in Central Europe .
features
Forest cockchafer grow to be 22 to 26 mm long. The color of the head and chest is usually brown, but it can also be significantly darker. This cockchafer also has the typical white hair triangles on the sides of the abdomen . The end of the abdomen ( telson ) is just as narrow as that of the field cockchafer , but the tip is somewhat knotty - somewhat less distinct in the female. When determining, a comparison with certain specimens is recommended. The third species in Central Europe is Melolontha pectoralis , whose telson ends bluntly and which only inhabits the extreme southwest.
distribution
The species is widespread Eurosiberian and prefers sandy forest areas and heather areas . In Europe , the forest cockchafer is particularly common in the east and north, including in the sandy areas of the Upper Rhine Plain . After mass occurrences ( calamities ) in southern Germany in recent years, the beetle has become more popular again, and information on its distribution is therefore being collected again.
Development and nourishment
The adult animals ( Imagines ) are in May and June active, d. In other words , they eat the first leaf shoots of oak and other deciduous trees (e.g. also maple and beech ) - if nothing is left, even conifers are not safe. The trees in the affected areas are full of beetles, which also regularly fly around and thus irritate visitors. The waste falls in large quantities from the trees, and a sound like light rain is created. These periodic mass occurrences help the forest cockchafer to avoid their natural enemies, since these cannot appear in the right place to the same extent. This type of protection against predators is even more developed due to the mass occurrence of the periodic cicadas of the genus Magicicada .
The trees, damaged by massive infestation, save themselves after their foliage has been destroyed with the so-called St. John's shoot .
The females of the beetles lay up to 30 eggs twice in the ground, where the larvae ( grubs ) feed on the roots of various plants over a three to five year development period.
Combat
Due to the long development period, there are always regional calamities that are fought by forestry, with the larvae causing the decisive damage. It is not uncommon for poisons to be used that kill far more than the beetles. To this day, the consequences are such. B. the use of DDT , also noticeable for humans. The Federal Biological Research Center for Agriculture and Forestry continues to pursue the goal of the most selective and limited control of the larvae, since the 1990s with fungal spores in southern Hesse. The problem has also increased in some parts of the country because the forests are already stressed for other reasons (water shortage due to lowering of the groundwater level, air pollutants, etc.).
Use
Not only humans have such mass occurrences in the past for themselves, z. They know how to use them, for example for feeding cattle, and the adult beetles and larvae serve as an important food source for numerous animals. Some insects living parasitically also depend on grubs, such as B. some species of predatory flies . Incidentally, a calamity reduces the growth in thickness of the affected tree, but harder wood is formed.
Web links
- Current research on the forest cockchafer in the Hessian-Bavarian border area - forest research at the LWF
- Occurrence and control
- Melolontha hippocastani at Fauna Europaea